Improvement in padlocks



tluitrll Stairs parte entre Letters Patent No. 99,116, dated January 25, 1870.

IMPROVEMENT IN PADLOCKS.

The Schedule referred to in these Letters Patept and 'making part of the same.

To all whom it may concernl Be it known that I, FRIEND W. SMITH, Jr., of Bridgeport, in theycounty of Faireld, and State of `Connecticut, have invented certain new and useful Improvements in Locks and Keys, of which the following is a full, clear, and exact description.

The object of the invention herein claimed is to render a lockunpickable; and

The improvements herein claimed consist- First, in combining a pivoted bit, passing into the barrel of a key, with a pin, on which the key turns, having an eccentric outline to cause the bit to assume,

when acting on the tumbler, au angle different from that which would be occupied bya rigid bit, this mode of construction rendering it very diiicult, if not irnpossible, to take an impression of the key without removing the bit from the barrel; and also rendering it very difficult to measure the length of the bit at the moment of acting on the tumbler.

Second, in combining bits pivoted eccentrically to the axis of the key, and oscillating in planes at right angles thereto, with an eccentric pin, against which the inner ends of thc pivoted bits press, and which pin causes the pivoted bits to assume various positions relatively to the axis of the key as it is turned in the lock. lhis invention constitutes an` improvement on that for which Letters' Patent of the United States, No. 87,518, were granted to me, March 2, 1,869. In

that pate-nt, the bits swung loosely on the outside of.

the barrel of the key, and did not come in contact with the pin, and the key had to be turned partially backward, to bring the bits into line with the key-hole, to permit the withdrawal of the key from the lock, but in this case this function is performed by the pin, the shaft of which causes the bits to assume the proper position as they come in line with the key-hole.

Third, in combining oscillating bits andan eccentric pin with tumblers, so shaped that the key will not act upon them during the lirst portion of its movement, but will then move them quickly and release them again, and, as the bits strike the tumblers suczessively, it is more diftcult to judge of their form :han it otherwise would be.

Fourth, in combining an eccentric pin, a key having oscillating bits, a series of spring-tumblers, and a springholt, so that the boit always remains shot, and the tumblers locked therewith until both are moved'by the positive action of the key.

ln the accompanying drawings my improvements are shown as adapted to a padlock, more especially designed for a mail-bag lock, which constitutes an improvement on Let-ters Patent, No. 86,377, granted February 2, 1869, to Frederick Egge.

Figure 1 represents a face view of my improved lock.

Figure 2, a similar view, with the front plate rcmoved, the bolt shot, and the key in the act of unlocking the lock.

Figure 3, a similar view, with the parts shown in the attitude they assume at the momept of completing the unlocking.

Figure 4, a view in perspective of the key, with a portion of the barrel broken away to show the projecting portion of the bits.

Figure 5, an end view of the pin and key.

The mechanism is enclosed -iu a case, A, having a notch, B, for the-insertion of the staple.

A bolt, C, moves across this4 notch.

This bolt is mounted una lever, D, oscillating on a pivot, d, shown in dotted lines in the drawing, and having an arm, d', projecting beyond the pivot.

A spring, c, forces the bolt across the notch when ever released from its catch, as hereinafter' explained.

Tumblers E, oscillate on a piv'ot, e, and are acted on on by springs, b.

A stud, n, on the bolt-lever, enters notches, h, as usual in locks of this class.

The key F may have one or more of its bits pivoted. In this instance, I have shown the two outer bits as fixed in the usual way', and the two inner ones, it', as oscillating on a pivot, j, eccentric to the axis ofthe key. The inner ends of the loose bits project through the key into its-barrel,.which is cut away for that purpose.

AThe pin G, of the lock, has a longitudinal slot or curved recess, g, cut in it, as shown in figs. 2, 3, and 5.

The operation ofthe lock is as follows:

Then unlocked, the head of the bolt Cproje-cts into the notch B. As the staple o f the mail-bag is inserted into the notch, it presses back the arm D,'and releases the stud n from the catchl, on one or vmore of the tumblers, which latter are immediately moved far enough by their springs to allow the stud a to escape from the notch 71, when the boltD is immediately'shot across the notch by its spring, and the bag is securely locked. This feature, however, is not claimed herein, asrit forms the subject-matter of another application for Letters Patent filed simultaneously herewith.

In unlocking theI bag, the key is inserted into the key-hole, and turned to the right. As soon as the bits abut against the tumblers, the pivoted bits fall y behind the iixed ones, as shown in fig. 2, until their inner ends bear against the bottom -of the groove in the pin, at which moment the key assumes the truek time moving the catch 1 forward Ito interlock with the stud, and hold the bolt G in its retracted position, as in fig. 3. The pivoted bits are generally broughtinto line with the fixed bits, by their inner ends bearing on the round surface of the pin, so that when the bits arrive opposite the key-hole, they are all in proper position for the withdrawal of the key.

It is obvious that my improvement may be adaptedv to locks, of forms and descriptions differing from that` herein shown and described.

I am aware that bits sliding transversely to the axis of the key have heretofore been combined with an ec-v ceitric pin,and therefore do not claim such a device.

claim', as my inventionv 1. The combination ofthe pivoted bit, passing into the barrel of the key, and the eccentric pin, these parts being constructed to operate substantially as hereinbefore set forth.

F. W. SMITH, JR.

Witnesses:

Jon I. PEYTON, WM. H. RUWE. 

